Composite lamination using array of parallel material dispensing heads

ABSTRACT

Aspects of the present disclosure include various exemplary embodiments of systems and methods relating to composite lamination using one or more arrays of parallel material dispensing heads. In one embodiment, a method of fabricating a high aspect ratio composite article generally includes applying a first strip material to a work surface datum at a first angle with a first material dispenser, and applying a plurality of second strip materials to a work surface datum each at a second angle with a plurality of rotatable parallel material dispensers. The method also includes advancing the first material dispenser and the rotatable parallel material dispensers as a unit the width of the second strip material and continuing application of the first strip material by the first material dispenser and a plurality of second strip materials by the rotatable parallel material dispensers until a desired length is reached.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/245,307 filed Oct. 6, 2005, which, in turn, is a divisionalof U.S. patent application Ser. No. 10/301,949 filed Nov. 11, 2002. Thisapplication is a continuation-in-part of U.S. patent application Ser.No. 10/301,949 filed Nov. 11, 2002. The disclosures of the aboveapplications are incorporated herein by reference.

FIELD

The present disclosure generally relates to composite lamination usingan array of parallel material dispensing heads.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Articles that are formed partially or wholly from composite materials(herein after referred to as “composite articles”) are employed in avast number of fields, usually to provide the finished article withdesired characteristics, such as a relatively low weight and arelatively high strength. One method of fabricating composite articlesincludes the use of strips of a composite material, such as a graphitetape or cloth, to form what is known in the art as a composite “lay-up”.The lay-up includes one or more layers, with each layer being formedfrom touching and/or overlapping strips of the material. A resin, whichmay be pre-impregnated in the material or later injected into one ormore of the layers of material, is later processed to cure the lay-upsuch that the material strips are bonded together. Typically, the lay-upis formed on a mandrel having a formed work surface that conforms to thedesired geometry of the finished composite article. Since the lay-up isrelatively flexible and unable to support itself prior to curing, themandrel is usually employed to support the lay-up during the curingprocess.

Known methods for the fabrication of composite articles include manualand automated fabrication. Manual fabrication entails manual cutting andplacement of material by a technician to a surface of the mandrel. Thismethod of fabrication is time consuming and cost intensive, and couldpossibly result in non-uniformity in the lay-up.

Known automated fabrication techniques include flat tape laminatingmachines (FTLM) and contour tape laminating machines (CTLM). Typically,both the FTLM and the CTLM employ a solitary composite materialdispenser that travels over the work surface onto which the compositematerial is to be applied. The composite material is typically laid downa single row (of composite material) at a time to create a layer of adesired width and length. Additional layers may thereafter be built uponto a prior layer to provide the lay-up with a desired thickness.FTLM's typically apply composite material to a flat transfer sheet orscrim. The transfer sheet and lay-up are subsequently removed from theFTLM and placed onto a mold or on a mandrel. In contrast, CTLM'stypically apply composite material directly to the work surface of amandrel.

The specifications for many composite articles further require that thecomposite material of each layer be applied in a predeterminedorientation, with the orientations of each layer being different. Tovary the orientation of the composite material in the layers, typicallyeither the tape dispenser is moved at different angles relative to themandrel or transfer sheet, or the mandrel or transfer sheet is manuallyshifted relative to the tape dispenser. The batch processing employed inknown automated tape laminating devices can be slow, tedious, andcumbersome. Therefore, there is a need for an automated process thatexpedites the fabrication of and increases the quality of compositelay-ups.

A wide variety of structures can be fabricated from laminated tape usingCTLM, FTLM, or manually. One such example is laminated tape aircraftstructures, many of which are prepared with CTLM, FTLM, or manuallylaminated tape. Because many existing CTLM and FTLM have a single tapedispensing head and a relatively low throughput (e.g., typically threeto five pounds per hour per machine), however, these machines can be abottleneck during aircraft product, especially for large commercialaircraft which can have thousands of pounds of composite structures.

SUMMARY

According to various aspects of the present disclosure, there areprovided various exemplary embodiments of systems and methods relatingto composite lamination using one or more arrays of parallel materialdispensing heads. One particular exemplary embodiment includes a methodof fabricating a high aspect ratio composite article. In thisembodiment, the method generally includes applying a first stripmaterial to a work surface datum at a first angle with a first materialdispenser and applying a plurality of second strip materials to a worksurface datum each at a second angle with a plurality of rotatableparallel material dispensers. The method also includes advancing thefirst material dispenser and the rotatable parallel material dispensersas a unit the width of the second strip material and continuingapplication of the first strip material by the first material dispenserand a plurality of second strip materials by the rotatable parallelmaterial dispensers until a desired length is reached.

Another exemplary embodiment of the present disclosure includes a devicefor fabricating a high aspect ratio composite article. In thisembodiment, the device generally includes a plurality of materialdispensers movable relative to a structure having a work surface datum.Each material dispenser is operable for applying strip material to thework surface datum along a predetermined axis. The plurality of materialdispensers includes at least a first material dispenser, at least asecond material dispenser in-line with the first material dispenser, anda plurality of material dispensers substantially parallel with eachother. The parallel material dispensers are disposed generally betweenand at an angle to the first and second in-line material dispensers. Thefirst and second in-line material dispensers are translatable relativeto the work surface datum such that the first and second in-linematerial dispensers can apply strip material to the work surface datumalong a predetermined axis, in one direction and then the oppositedirection. The parallel material dispensers are rotatable about avertical axis and translatable relative to the work surface datum suchthat the parallel material dispenses can be rotatably positioned forapplying strip material at predetermined axes that are not parallel tostrips applied by the first and second in-line material dispensers.

A further exemplary embodiment of the present disclosure includes amethod of fabricating a high aspect ratio composite article. In thisembodiment, the method generally includes applying a plurality of stripmaterials to a work surface datum each at an angle with a plurality ofparallel material dispensers by selectively cutting predeterminedlengths of the strip materials, without cutting backing material, at anangle corresponding with the angle at which the plurality of stripmaterials will be applied to the work surface datum, positioning the cutpredetermined lengths of strip materials for placement to the worksurface datum, and applying the cut predetermined lengths of stripmaterials to the work surface datum without moving the parallel materialdispensers as a whole. The method also includes advancing the parallelmaterial dispensers as a unit the width of the strip material andcontinuing application of a plurality of strip materials by the parallelmaterial dispensers until a desired length is reached.

Further aspects and features of the present disclosure will becomeapparent from the detailed description provided hereinafter. Inaddition, any one or more aspects of the present disclosure may beimplemented individually or in any combination with any one or more ofthe other aspects of the present disclosure. It should be understoodthat the detailed description and specific examples, while indicatingexemplary embodiments of the present disclosure, are intended forpurposes of illustration only and are not intended to limit the scope ofthe present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a perspective view of a composite fabrication deviceconstructed in accordance with an exemplary embodiment of the presentdisclosure;

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. 1 andillustrates components of an exemplary material dispensing headaccording to an exemplary embodiment of the present disclosure;

FIG. 3 is a plan view of a layer of strip material applied to a worksurface datum in accordance with one exemplary embodiment of the presentdisclosure;

FIG. 4A is a schematic illustration showing the fabrication of anexemplary composite lay-up on a mandrel;

FIG. 4B is a schematic illustration showing the fabrication of anexemplary composite lay-up on a transfer sheet;

FIG. 5 is a perspective view of a portion of an exemplary materialdispenser illustrating the cutter and idler drum;

FIG. 6 is a partially broken away plan view of the composite lay-up ofFIG. 1 illustrating the various layers of strip material and theirorientations;

FIG. 7 is a perspective view of another exemplary embodiment of thepresent disclosure showing dual support bases in an active and anon-active area and a processing station;

FIG. 8 is a partial overhead view of another exemplary embodiment of agantry and material dispenser configuration in accordance with thepresent disclosure;

FIG. 9A is an overhead view of another exemplary gantry, turntable, andmaterial dispenser configuration according to an exemplary embodiment ofthe present disclosure;

FIG. 9B is an overhead view of the embodiment shown in FIG. 9A afterstrip material has been laid down by the material dispensers to form afirst portion of the composite lay-up on the turntable;

FIG. 9C is an overhead view of the embodiment shown in FIG. 9B after theturntable has been rotated one hundred eighty degrees and after stripmaterial has been laid down by the material dispensers to form thesecond portion of the composite lay-up;

FIG. 10 is an overhead view of an exemplary embodiment of a compositefabrication device having left and right zero degree material dispensingheads and an array of six material dispensing heads deployed along alength of a lay-up table and capable of collectively swiveling;

FIG. 11 is an overhead view of the composite fabrication device shown inFIG. 10 with the array of six material dispensing heads positioned at aninety degree echelon;

FIG. 12 is an overhead view of the composite fabrication device shown inFIG. 10 with the array of six material dispensing heads positioned at anegative forty-five degree echelon;

FIG. 13 is a partial perspective view of an exemplary embodiment of thematerial composite fabrication device including an array of swivelingmaterial dispensing heads and a zero degree non-swiveling materialdispensing head according to an exemplary embodiment of the presentdisclosure;

FIG. 14 is a cross-sectional view showing components of an exemplarymaterial dispensing head according to an exemplary embodiment of thepresent disclosure;

FIGS. 15A through 15C are schematic illustrations of an exemplary kisscutting device capable of cutting strip material at different anglesaccording to an exemplary embodiment of the present disclosure;

FIG. 16A is an overhead view of another exemplary gantry and materialdispenser configuration according to an exemplary embodiment of thepresent disclosure; and

FIG. 16B is an overhead view of the gantry and material dispenserconfiguration shown in FIG. 16A after the array of material dispensingheads have been swiveled or rotated.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the present disclosure, application, or uses.

According to various aspects of the present disclosure, there areprovided composite lamination devices having an array or stack ofmodular material dispensing heads configured to operate parallel to oneanother. Such composite lamination devices may include materialdispensers specifically arranged and tailored for producing compositearticles within particular part families. For example, one exemplaryembodiment includes material dispensing heads configured for producinghigh aspect ratio composite articles, such as stringers, narrow spars,floor beams, etc. Another exemplary embodiment includes materialdispensing heads configured for producing relatively large parts andparts with low aspect ratios, such as ribs, wheel bulkheads, empennagepanels, and other large parts. Yet another exemplary embodiment includesmaterial dispensing heads configured for producing wide-to-narrow spars,very long and wide parts (e.g., wing panels, spars, etc.) and drape-ableskins.

In addition, various embodiments can provide a modular configuration forthe material dispensing heads, which, in turn, can lead to improvedproductivity by enabling depleted or failed material dispensing heads tobe quickly replaced. In various embodiments, the multiple simultaneouslaminations and ability for the material dispensing heads to be cleanedand replenished offline can improve machine productivity (and in somecase) by as much as an order of magnitude higher than many existing CTLMand FTLM systems. Some embodiments can also include plus or minusforty-five degree cutting capability.

In various embodiments (examples of which are shown in FIGS. 10 through16 and described below), a material lamination device is provided thatis well-suited for producing wing stringers, floor beams, narrow spars,and other high aspect ratio parts. In these particular embodiments, anarray or stack of material dispensing heads is deployed along a table'slength (X-axis). The stack of heads can collectively swivel as a group,for example, to a positive forty-five degree echelon (e.g., FIG. 10), aninety degree echelon (e.g., FIG. 11), a negative forty five degreeechelon (e.g., FIG. 12), among other angular settings.

Non-swiveling heads can also be used to dispense zero degree stripmaterial or plies. Accordingly, various aspects of the presentdisclosure can provide improved tape laying machines and methodswell-suited for fabricating long narrow composite components, such aswing stringers and spars, floor beams, among other high aspect ratiocomposite articles.

Various other embodiments include a gantry with non-rotatable materialdispensing heads disposed above a rotary turntable, which is used forsupporting and rotating the work piece relative to the materialdispensing heads. An example of one such embodiment is shown in FIG. 1and described herein. These exemplary embodiments can be useful forproducing large parts such a ribs, bulkheads, empennage panels, andother large parts.

Additional embodiments include an array or stack of material dispensingheads generally positioned in a rank and carried on an X-Y gantry. Insome of these embodiments, the array of heads may be rotatable between apositive forty-five degree and a negative forty-five degree echelon. Anexample of one such embodiment is shown in FIGS. 16A and 16B anddescribed herein. These exemplary embodiments can be useful forproducing very long and wide parts, such as wing panels and spars, amongothers.

Further embodiments include an array or stack of material dispensingheads carried on a rotary unit, which, in turn, is suspended from an X-Ygantry. The X-Y gantry is disposed above a fixed table. An example ofone such embodiment is shown in FIG. 8 and described herein. Theseexemplary embodiments can be useful for producing very long and wideparts, such as wing panels and spars, among other long and wide partswhere the part size would require the turntable for the entire part tobe so large as to be impractical.

FIG. 1 illustrates a composite fabrication device 12 constructed inaccordance with one embodiment of the present disclosure. In thisparticular illustrated embodiment, the composite fabrication device 12includes a structure 14 having a work surface datum (a work surface) 16.The composite fabrication device 12 has a gantry 18 elevated over thework surface datum 16. In the example provided, the gantry 18 includestwo vertical beams 20 and a bridge rail 22. Alternatively, the gantry 18may be constructed in numerous other ways including a pair of overheadrunways or beams (not shown) that support the opposite ends of thebridge rail 22.

The vertical beams 20 are associated with a pair of tracks 24 that boundthe opposite sides of a working area 26. For purposes of discussion, thetracks 24 define a X-axis that is generally perpendicular to a Y-axisdefined by the bridge rail 22. The vertical beams 20 can move along thetracks 24, thus the tracks 24 may be, for example, rails over whichwheels (not shown) attached to the vertical beams 20 travel. The gantry18 can be selectively propelled along the tracks 24 by a suitable drivemechanism 25, which may be a servo tractor or any drive mechanism knownin the art. The bridge rail 22 is attached to the vertical beams 20,either in a fixed position or such that it has vertical mobility withrespect to the structure 14 below. In the latter instance, the bridgerail 22 is permitted to move vertically to adjust the position of thebridge rail 22 relative to the structure 14 that is located beneath thegantry 18. Translation of the gantry 18 on the tracks 24 and, if thegantry 18 is equipped as such, vertical movement of the bridge rail 22may be automatically and/or manually controlled. The compositefabrication device 12 can include a control processing unit, or acontroller 15, that interfaces with the drive mechanism 25 and thegantry 18 and its several components. In view of the extent of thedisclosure, a detailed discussion of the construction and operation ofthe controller 15 need not be provided herein as such controllers 15 arewell within the capabilities of one skilled in the art.

An anterior end 28 and a posterior end 30 of the working area 26 arebounded by end tracks 32. Within the working area 26, the structure 14may be placed upon or incorporated into a support base 34. In accordancewith an aspect of the present embodiment, the support base 34 isrotatable relative to the bridge rail 22. Such rotation can be achievedby placing the support base 34 on a rotary turntable 80 or incorporatinga conventional rotary drive mechanism 80a into the support base 34.Thus, the work surface datum 16 of the structure 14 may have itsorientation changed by rotating the rotary turntable 80 in the exampleprovided. Alternatively, the support base 34 may have a fixed positionand the gantry 18 may be moved (e.g., rotated) or the movement of thebridge rail 22 rotated and controlled along both the X and Y axes tochange the orientation with which material is laid onto the work surfacedatum 16 as will be discussed in greater detail below.

A plurality of material dispensers 36 are attached (directly and/orindirectly) to opposite sides 58 and 60, respectively, of the bridgerail 22. The material dispensers 36 may also be attached to only asingle side (58 or 60) of the bridge rail 22, if adjacent materialdispensers 36 are oriented to dispense material in opposite directions.The material dispensers 36 apply material strips 62 (such as forexample, carbon fiber pre-impregnated resin tapes or cloth, etc.) to thework surface datum 16 of the structure 14. The position of materialdispensers 36 along the bridge rail 22 is fixed such that the materialdispensers 36 are attached at predetermined positions along the bridgerail 22. In an alternate embodiment, the position of the materialdispensers 36 may be adjustable and the position of the materialdispensers 36 may be translated relative to one another along the bridgerail 22 to accommodate a variety of differently sized strip materials 62and material dispenser 36 configurations, as shown in FIGS. 1 and 2. Thematerial dispensers 36 may be translated along the bridge rail 22 by anyknown method in the art. One exemplary method is to attach the materialdispensers 36 to a track 65 along the bridge rail 22. Locking mechanisms67 on the material dispensers 36 lock the position of each materialdispenser 36 during operation. Release of the locking mechanisms 67allows movement of the material dispensers 36 to new positions along thebridge rail 22. The bridge rail 22 and track 65 may also permitintroduction or removal of material dispensers 36, as necessary.

An exemplary configuration for the present embodiment includes staggeredmaterial dispensers 36 on the sides 58, 60 of the bridge rail 22, asshown in the example of FIG. 1. Each material dispenser 36 has a housing52 containing rolled strip material 62. Since the housing 52 typicallyis wider than the width of the strip material 62, the staggeredconfiguration allows applied strip materials 62 to abut or only havesmall gaps (e.g., less than one-half the width of strip material 62,etc.) in between. Thus, a material dispenser 36 on the first side 58 ofthe gantry 18 is situated with respect to a material dispenser 36 on thesecond side 60 so as to allow the strip material 62 to be applied in analternating strip pattern. The amount of distance between edges 71 ofstrip material 62 is a function of the distance between the materialdispensers 36 and is chosen based upon various design criteria for thecomposite lay-up that is to be fabricated. The position of the edges 71of the strip material 62 relative to one another may range from a smallgap to no overlap (i.e., abutting) to over one-half the width of thestrip material 62. The distance between the material dispensers 36 maybe adjusted (e.g., via the track 65 and locking mechanisms 67, etc.) toprovide the desired degree of overlap. In an alternate embodiment, thematerial dispensers 36 may be fixed along the bridge rail 22, and thebridge rail 22 may move a short distance along the Y axis (i.e. lessthan the width of the strip material 62) to thereby enable similar stripmaterial layers to overlap previously applied layers of strip material62 in the same orientation.

With reference to FIG. 2, material dispensers 36 are illustrated ascoupled to the bridge rail 22. For purposes of discussion, a first one64 of the material dispensers 36 is coupled to the first side 58 of thebridge rail 22, and a second one 66 of the material dispensers 36 iscoupled to the second side 60. Each material dispenser 36 operablyhouses strip material 62 that is rolled onto a spool 90 in the materialdispenser housing 52. Such strip material 62 on a spool 90 mayoptionally be held in a separate cartridge (not shown) contained withinthe housing 52. The strip material 62 can have a backing paper 92 toinhibit undesirable blocking of the strip material 62 during release.The strip material 62 can be cut prior to approaching a release region94 wherein the strip material 62 is applied to the work surface datum16.

With continued reference to FIG. 2, the material dispenser 36 also has acutter 102 for cutting the strip material 62. Such cutters 102 may befor example, blade or laser cutters. One exemplary embodiment of acutter 102 is shown in FIGS. 2 and 5, where a cutter drum 104 has asurface 108 with a single cutter blade 106 protruding and extendingalong the entire length of the cutter drum 104. As strip material 62 isapplied to the work surface datum 16, the blade 106 faces away from thearea 110 where strip material 62 passes. As the strip material 62 isunrolled, it passes over an idler drum 112, which directs it towards arelease region 114. The strip material 62 passes between the idler drum112 on one side and a cutter drum 104 on the other side. The cutter drum104 sits stationary with the cutter blade 106 facing away from the stripmaterial 62 passing by, that is, unless a cut in the strip material 62is necessary. Then, the cutter drum 104 is actuated and rolls towardsthe strip material 62 to cut it. This type of cutter drum 104 enablescutting to be accomplished continuously without interrupting theapplication of strip material 62. The cutter drum 104 is configured suchthat the strip material 62 is cut while leaving the backing paper 92intact. The backing paper 92 continues to be wound onto a collectorspool 116. The collector spool 116 may also be optionally contained in acartridge (not shown) in the housing 52 with the roll 90 of stripmaterial 62. The backing paper 92 draws the strip material 62 into therelease region 114 of the material dispenser 36. The backing paper 92facilitates movement and smooth application of the strip material 62along the work surface datum 16.

An alternate embodiment of the cutter drum 104 of the present disclosureincludes a helical configuration blade (not shown) that enables angledcuts to be made while the cutter drum 104 rotates towards the stripmaterial 62. When the cutter blades 106 for each material dispenser 36make straight cuts across the strip material 62, the resulting stripmaterial composite lay-up has edges that are serrated or crenulated.Such a composite lay-up can later be trimmed, usually after curingoccurs in the lay-up mandrel, to achieve a straight finished edge forthe finished composite article. Other exemplary embodiments of cuttingapparatus and devices are shown in FIGS. 15 and 16 and described herein.

In the illustrated embodiment of FIG. 2, the strip material 62 andbacking paper 92 are compressed or smoothed against the work surfacedatum 16 by a primary compactor or shoe 96, which is retractable (i.e.capable of descending from a bottom surface 98 of the material dispenser36 and also capable of at least partially retracting above the bottomsurface 98 of the material dispenser 36). Further, the primary compactor96 optionally has a degree of freedom of rotational movement asdesignated by arrow R that enables the primary compactor 96 to adapt toangles or contours along the work surface datum 16. This freedom ofmovement may be necessary when the structure 14 is a contoured lay-upmandrel. The material dispenser 36 optionally has a trailing compactor100, which may further assist in smoothing the strip material 62 alongthe work surface datum 16, especially at terminal edges 74 (FIG. 1) ofthe strip material 62 after it is cut. Both the primary and trailingcompactors 96, 100 (FIG. 2) retract when the material dispenser 36 isnot in use, and the movements of the primary and trailing compactors 96,100 can be automated by computerized controls.

Strip materials 62 may include fiber reinforced composites, polymers(e.g. adhesives or laminates), and metal foil, although the presentdisclosure is not limited to the materials listed above, but rather isadaptable to any strip material. As those skilled in the art willappreciate, material selection for the strip material 62 is dependent onthe application in which the composite article will be used, anddifferent strip materials 62 may be applied in alternate layers toprovide the composite lay-up with desired characteristics.

Fiber reinforced composite materials are generally categorized as tape,woven cloth, non-woven cloth, paper, and mixtures thereof. “Tape”generally refers to and includes uniaxial reinforcement fibers thatextend along a single axis of the strip material. The term “cloth”generally refers to and includes reinforcement fibers laid along atleast two different axes within the strip material. Cloth iscommercially available as bi-axial, tri-axial and quad-axial, indicatingfibers extending in two, three, or four different axes, respectively.The fibers may optionally be woven with one another, or may bemanufactured as non-woven cloth. A vast array of composite reinforcementfibers are commercially available, such as for example, carbon, Kevlar®fibers, glass, and mixtures thereof. Metal foils are also known in theart, and may be included in composite articles. Such metal foils arefrequently interspersed as material layers within a lay-up composite.Strip materials are commercially available in a wide variety of widths.One common width for fiber reinforced material strips is six inches.Aspects of the present disclosure contemplate and are adaptable to avariety of strip material widths, and material dispensers 36 may bere-positioned along the gantry 18 to accommodate different stripmaterial widths. In addition, the dimensions set forth in this paragraph(as are all dimensions set forth herein) are mere examples and can bevaried depending, for example, on the particular application.

The term “composite article” generally refers to and includes a materialthat includes a composite resin matrix, wherein the resin includes atleast one polymer or mixtures of polymers, and fibers or particles thatare distributed throughout to form the matrix or composite. Stripmaterial 62 is available in both resin pre-impregnated andnon-impregnated configurations. A pre-impregnated resin strip material62 (generally referred to as “pre-preg”) has resin added into the stripprior to spooling it onto rolls. When a non-impregnated strip material62 (generally referred to as “dry fiber”) is employed, a resin istypically added in a subsequent processing step. Non-impregnated stripmaterials 62 typically employ a tackifier or adhesive (typically apolymer) that facilitates adhesion of the strip material 62 layers tothe work surface datum 16 or other previously applied layers of stripmaterial 62. Processing methods that subsequently add the resin into thelayers of strip material 62 are well known in the art and include, forexample, vacuum assisted resin infusion into the strip material 62.

Returning to FIG. 1, the material dispensers 36 are changed out when thesupply of strip material 62 is exhausted or a different layer of stripmaterial 62 is needed for the composite lay-up. In this particularillustrated embodiment, material changers 40 can service the materialdispensers 36 to replace an entire material dispenser 36. The materialchangers 40 may optionally change only material cartridges (not shown)contained within the housing 52 of the material dispensers 36. Thus, itis contemplated that the material changers 40 may optionally change outan entire material dispenser 36 (including a housing 52), or thematerial changers 40 may change out only a material cartridge of amaterial dispenser 36 thus leaving the housing 52 and material dispenser36 attached to the bridge rail 22. The example shown in FIGS. 1 and 2depicts material changers 40 that replace the entire material dispenser36. But either configuration of material changer 40 is feasible andcontemplated for various embodiments of the present disclosure.

In an exemplary embodiment, one or more mobile modular material changers40 translate along each end track 32 to service the plurality ofmaterial dispensers 36 that are located on an associated side of thebridge rail 22. The end tracks 32 are adjacent to changing stations 38which service the mobile material changers 40 and provide a repositoryfor used and new material dispensers 36. The mobile modular materialchangers 40 hold a replacement material dispenser 36 for replenishing orchanging the strip material 62 in the material dispensers 36 attached tothe gantry 18.

The mobile modular material changer 40 can be automated and interfacewith the gantry 18 to replace a designated material dispenser 36 when,for example, the material in a given material dispenser 36 hasdiminished to a predetermined level or a different strip material 62 isto be applied. The gantry 18 is moved to either the anterior end 28 orposterior end 30 so it is next to one of the end tracks 32. The materialchanger 40 moves laterally along the end track 32 so that it approachesthe individual material dispenser 36 requiring service. Such a materialdispenser 36 may be selected based on an output signal from the materialdispenser 36 itself indicating that the amount of strip material 62 islow or may be automatically or manually selected to change the stripmaterial 62 within the composite lay-up being formed. The materialchanger 40 has a receiving region 54 to place a spent or used materialdispenser 36 into. The material changer 40 also has a replacement region56 for storing the “new” material dispenser 36 so that it is availablefor placing into location at which the “old” material dispenser 36 hasbeen removed.

The material changer 40 engages the material dispenser 36, interfaceswith the gantry 18 as necessary to release the quick connect 68 which iseither interconnected directly with the bridge rail 22 (not shown) oralternately with the track 65 and locking mechanism 67, and removes thematerial dispenser 36. The material changer 40 places the “old” materialdispenser 36 into the receiving region 54, and acquires a “new” materialdispenser 36 which it attaches to the bridge rail 22. Alternately, thematerial replenishing and/or changing operation may be accomplishedmanually. In such an embodiment, changing stations 38 and end tracks 32would not be necessary components.

The material dispensers 36 can be attached either directly to the chairrail 22, or attached to the track 65 on the chair rail 22, via acoupling 68, as shown in FIG. 2. One exemplary type of coupling 68 is aquick release connection generally known as a “quick connect”, such as aQuick Change 300, which is commercially available from EOA Systems,Inc., located in Carrollton, Tex. Further, if only a cartridge (notshown) is removed from the material dispenser 36, it can be coupled tothe housing 52 by a quick connect. As those skilled in the art willappreciate, however, suitable couplings and quick connects are wellknown in the art and as such, the scope of the present disclosure is notlimited to the exemplary coupling discussed and illustrated herein. Ifthe first and second material dispensers 64, 66 are attached to thetrack 65 that permits movement of the material dispensers 64, 66 alongthe bridge rail 22, the releasable locking mechanism 67 locks thematerial dispensers 36 in place.

As shown generally in FIGS. 1 and 2, each of the first and secondmaterial dispensers 64, 66 is employed to apply strip material 62 to thework surface datum 16 of the structure 14. A pattern of multiplematerial strips 62 applied onto the work surface datum 16 by theplurality of material dispensers 36 on the first and second sides 58, 60of the bridge rail 22 form a layer 82. An out stroke of the bridge rail22 from the starting point 81 to the ending point 83 enables thematerial dispensers 36 to apply strip material 62 in a first direction70, where each material strip 62 is substantially parallel with oneanother. The return or back stroke that occurs as the bridge rail 22travels in a reverse direction from the ending point 83 back to thestarting point 81 enables strip material 62 to be laid in parallel alonga predetermined axis by the second material dispensers, as shown by 72.A single round trip stroke of the gantry 18 creates an entire layer ofmaterial 82 composed of material strips 62 all parallel with oneanother.

The gantry 18 moves across the working area 26 over the structure 14 ina first direction 70 (i.e., an out stroke) and returns in a seconddirection 72 (i.e., a return stroke) laying strip material 62 along apredetermined axis. Although the gantry 18 may move over the entireworking area 26 which spans from the anterior end 28 to posterior end30, the gantry 18 may alternatively only move over small regions of theworking area 26. Thus, during operation when strip material 62 is beingapplied, the gantry 18 is capable of traveling a shortened distancealong the tracks 24. This can be advantageous where a structure 14 andits work surface datum 16 are relatively small in comparison to theoverall work area 26, and the gantry 18 may only need to move partiallyalong the tracks 24 from a starting position or point 81 at the front ofthe structure 14 to an ending position or point 83 at the end of thestructure 14. Partial translation of the gantry 18 along the tracks 24can facilitate faster application of strip material 62 along apre-determined axis to the work surface datum 16.

With reference to FIG. 3, in this particular illustrated configuration,strip material 62 is applied in a first direction 70 (via the firstmaterial dispensers 64 in FIG. 2) and a second direction 72 (via thesecond material dispensers 66 in FIG. 2), wherein the second direction72 is opposite the first direction 70. Each edge 71 of strip material 62interfaces with (e.g., comes into close proximity with by either havinga small gap or abutting) another edge 71 of another strip material 62that was applied in the opposite direction. The junction lines 75, 77indicate where the edges of strip material 62 applied in a firstdirection 70 approach and/or abut the edges of the strip material 62applied in a second direction 72.

FIGS. 4A and 4B illustrate various alternatively constructed structures14. The structure 14 shown in FIG. 4A is a lay-up mandrel 87. The lay-upmandrel 87 may be a template or mold that defines the work surface datum16 onto which the strip material 62 is laid. Depending on the particularapplication, the work datum surface 16 of the lay-up mandrel 87 may haveonly slight to moderate contours, such that the primary compactor 96 andtrailing compactor 100 (FIG. 2) can pivot at slight to moderate anglesto follow the contour in a manner such that the strip material issmoothed against the work surface datum 16. Typically a maximum grade orangle the compactors 96, 100 can accommodate is about a fifteen percentincline. After the strip material 62 application is complete (all of thelayers have been laid onto the work surface datum 16 to thereby form acomposite material lay-up 91), the lay-up mandrel 87 is removed from theworking area 26 (FIG. 1) and further processed. For example, furtherprocessing may include adding polymer resin to the composite materiallay-up 91 through vacuum injection processing and/or curing orcross-linking the strip material 62 that makes up the composite materiallay-up 91 through autoclaving or baking. After processing, the compositearticle (not shown) is removed from the lay-up mandrel 87, where it maybe trimmed and/or machined as necessary.

The structure 14 shown in FIG. 4B is a transfer sheet 89, which is alayer of material that provides a surface on which to apply stripmaterial 62. Depending on the particular application, the transfer sheet89 may be sufficiently large such that several persons are needed tomanually move (e.g., lift and carry, etc.) the transfer sheet 89 andlay-up 91 thereon. As with the lay-up mandrel 87 shown in FIG. 4A, thestrip material 62 is applied in multiple layers to form a lay-up 91 onthe transfer sheet 89 (FIG. 4B). After application of the strip materiallay-up 91 is completed, the transfer sheet 89 can be transferred to aseparate lay-up mandrel (not shown) having the desired contour for thecomposite article, and the strip material lay-up 91 is cured. Thetransfer sheet 89 may be designed to be removed from the lay-up 91, suchas, for example, a removable paper backing as is known in the art. Thetransfer sheet 89 may alternatively be incorporated into the compositearticle or a part, forming, for example, an exterior or interior surfaceof the composite article. Incorporated transfer sheets 89 may be, forexample, scrim cloth or fiberglass cloth, which may have lateradvantages if the composite part is machined. For example, theincorporated transfer sheet 89 may protect against splintering of thecured composite article when it is subjected to drilling or machining,and further may provide a smoother exterior finish. Subsequentprocessing of the lay-up 91 (with or without the transfer sheet 89) canbe similar to the processing of the lay-up 91 when the mandrel 87 inFIG. 4A is used as the structure 14.

With continued reference to FIG. 1, one aspect of a exemplary embodimentof the present disclosure includes the support base 34, which can bemounted on the rotary turntable 80, wherein the orientation of the stripmaterial 62 forming a layer 82 as applied to the work surface datum 16can be selectively changed between layers 82 of the strip material 62.Composite reinforced materials having a single reinforced fiberdirection (e.g., uniaxial tape) exhibit anisotropic characteristics,which usually mean that they typically exhibit relatively high strengthalong the primary axis of the reinforcement fibers, but do not exhibitthe same strength along other axes. Thus, depending on the selection ofstrip materials and the application in which the composite reinforcedmaterial is used, it may be necessary for the composite material toexhibit isotropic or uniform strength in multiple directions for severalpredetermined axes. As discussed previously, when multiple materiallayers are laid upon the work surface datum 16 they are generallyreferred to as “lay-up”. When the support base 34 is rotated betweenmaterial layers 82, the lay-up has different orientations, such as theexemplary composite material shown in FIG. 6.

In the particular example provided in FIG. 6, a first layer 84 includesmultiple material strips applied to the work surface datum 16 such thateach strip 62 of this first layer 84 is laid along an axis that isparallel to a first predetermined axis A as formed by movement of thebridge rail 22 along the X axis. A second layer 86 of strip material 62is applied over the first layer 84 such that each strip 62 of thissecond layer 86 is applied along an axis that is parallel to a secondpredetermined axis B, which is rotated at positive forty-five degreesfrom axis A. To accommodate this change, the support base 34 is rotatedcounter-clockwise forty-five degrees from the zero degree position. Athird layer 88 of strip material 62 is applied over the second layer 86,such that each strip 62 of this third layer 88 is applied along an axisthat is parallel to a third predetermined axis C, which is rotatednegative forty-five degrees from axis A. To accommodate this change, thesupport base 34 is rotated clockwise forty-five degrees from the zerodegree position (i.e., ninety degrees clockwise from the positiveforty-five degree position). The location of the zero degree positionrelative to the work surface datum 16 is established by thespecifications for the composite article. In one exemplary embodiment ofthe present disclosure, the rotary turntable 80 is automated via theconventional rotary drive mechanism 80a of a type that is well known inthe art. The operation of the rotary turntable 80a can be integratedwith the application of strip material 62 from the material dispensers36. Further, as recognized by one of skill in the art, variousconfigurations and angles may be selected for a composite materiallay-up 91. As such, the example just described and shown in FIG. 6 isnot intended to limit the scope of the present disclosure.

Multiple layers of the strip material applied over the work surfacedatum 16 (the composite material lay-up 91) can have layers 82 of stripmaterial 62 ranging from four to over one-hundred. In one exemplaryembodiment of the present disclosure, the strip material 62 has a widthof about sixth inches and creates a swath of material strips having anoverall width of approximately fifteen feet (where there are fifteenmaterial dispensers on each side of the gantry 18, or thirty totalmaterial dispensers when counting both gantry sides). An exemplary rangefor the number of layers 82 for the lay-up 91 is between about twentyand forty layers.

FIG. 7 illustrates an alternately constructed composite fabricationdevice 12′, wherein the material dispensers 36 apply strip material 62to at least two structures 124 having work surface datums 16 a′ and 16b′. The several components of the composite fabrication device 12′(e.g., material changers 158, etc.) can be controlled similarly to thosedescribed in previous embodiments by a controller 15′. A first andsecond structure 128 and 130 rest on a first support base 132 within thework area 134 in an active area 144. A non-active area 145 within thework area 134 can be identically configured to the active area 144. Thenon-active area 145 has a third and fourth structure 136 and 138 restingon a second support base 140.

A gantry 18′ configuration can be substantially the same structurallyand operably as those described in previous embodiments. As shown inFIG. 7, the gantry 18′ has a plurality of material dispensers 36 thatapply strip material 62 to the work surface datums 16 a′, 16 b′. Thegantry 18′ applies strip material 62 to the first and second structures128, 130 on the first support base 132 in active area 144. The secondsupport base 140 with the third and fourth structures 136, 138 are inthe non-active area 145, where the gantry 18′ is not operating. Thisillustrated embodiment permits two separate working areas 144, 145 forthe gantry 18′ and material dispensers 36. Thus, while the gantry 18′ isworking over the first support base 132, the second support base 140 maybe accessed for other activities aside from strip material application.This configuration can be particularly advantageous where the structure124 has lay-up applied (e.g., the transfer sheet or lay-up mandrelitself) and must be transferred to another station for furtherprocessing.

As shown in FIG. 7, two separate transfer sheets 136 and 138 are shownplaced on the second support base 140. The third and fourth transfersheets 136, 138 can be transferred and placed on a lay-up mandrel 152(for simplicity only a single lay-up mandrel is depicted in FIG. 7). Thelay-up mandrel 152 can be cured or cross-linked in a processing chamber154. Such a processing chamber 154 is typically a heat oven or anautoclave chamber. The configuration of multiple support bases 132, 140in this particular embodiment can permit continuous material dispenser36 application and increases work efficiency over a single support base(132 or 140), where operations must be ceased to remove and place a newstructure 124 onto the support base (e.g., 132 or 140).

FIG. 8 is a partial overhead view of a composite fabrication device 12″constructed in accordance with the teachings of another alternateembodiment of the present disclosure. As shown, the compositefabrication device 12″ includes a gantry 18″ having four vertical beams20″, a pair of spaced-apart bridge rails 22″, a pair of lateralstabilizers 300, and a rotary dispensing unit 302 suspended from thebridge rails 22″. Each bridge rail 22″ is coupled to a pair of thevertical beams 20″. Each lateral stabilizer 300 is coupled to a pair ofvertical beams 20″. The gantry 18″ can be movable on the tracks 24 in amanner that is similar to that described above for the embodiment shownin FIG. 1.

With continued reference to FIG. 8, the rotary dispensing unit 302includes an arcuate outer track 308 and a rail 310 to which the materialdispensers 36 are mounted. The rail 310 may be similar to the track 65(FIGS. 1 and 2), and the material dispensers 36 can be removably andadjustably coupled to the rail 310 through conventional quick connects68 in a manner similar to that described above. The bridge rails 22″support the outer track 308 for rotation thereon. The rotation of theouter track 308 can be controlled via a conventional and well knownrotary drive mechanism 320. The rail 310 is fixed to the outer track308. Alternately, the outer track 308 may be non-rotatably supported bythe bridge rails 22″, and the rail 310 may be rotatably coupled to theouter track 308.

In the illustrated embodiment of FIG. 8, a linear drive mechanism 322 isfurther provided to control the movement of the rotary dispensing unit302 along the Y axis on the bridge rails 22″. The linear drive mechanism322, rotary drive mechanism 320, and drive mechanism 25 can becoordinated by a controller 15″ so that the axis 332 of the rotarydispensing unit 302 may be accurately positioned rotationally andthereafter moved in the X and Y directions to dispense strip material 62into the work surface datum 16 along a desired axis.

In the particular embodiment illustrated, a first layer 330 was appliedwith the rotary dispensing unit 302 in a zero degree orientation. Then,the rotary dispensing unit 302 was rotated clockwise to a negativeforty-five degree angle with respect to the zero degree axis reference,and the gantry 18″ traveled along the X and Y directions to apply asecond layer. As appreciated by one of skill in the art, the gantry 18″may travel only partially along the tracks 24 to apply strip material 62at an angle, rather than full strokes from one end to the other. Due tothe highly synchronized movements in some embodiments of the presentdisclosure, such embodiments may be fully automated with computerizedcontrol systems. Other aspects of this embodiment shown in FIG. 8 can besimilar to aspects described herein for other embodiments, such asautomatic material replacement by material changers (e.g., materialdispenser changers 40 shown in FIG. 1, etc.).

FIGS. 9A through 9C are overhead views showing another exemplaryembodiment that includes a gantry 418 supporting an array of materialdispensing heads 436 generally above a rotary turntable 480. As shown,the gantry 418 is configured for translatable movement along the tracks424. The tracks 424 bound the opposite sides of the working area 426.

During operation, the gantry 418 can translate along the tracks 424 andmove across the entire working area 426 in a first direction (i.e., anout stroke) and return in a second direction (i.e., a return stroke).During this translation of the gantry, one or more of the materialdispensing heads 436 can apply strip material along a predeterminedaxis. Although the gantry 418 may move over the entire working area 426,the gantry 418 may alternatively only move over small regions of theworking area 426. Thus, during operation when strip material 462 isbeing applied, the gantry 418 may be capable of traveling a shorteneddistance along the tracks 424. This can be advantageous, such as, forexample, in FIG. 9B where the work surface datum 416 is relatively smallin comparison to the overall work area 426, and the gantry 418 may onlyneed to move partially along the tracks 424 from a starting position forthe composite lay-up to an ending position for the composite lay-up.Partial translation of the gantry 418 along the tracks 424 canfacilitate faster application of strip material 462 along apre-determined axis to the work surface datum 416.

In addition, not all of the material dispensing heads 436 need to beapplying strip material 462 as the gantry 418 moves along the tracks424. Instead, the material dispensing heads 436 can be selectivelyoperated at different times for applying strip material 462 in aparticular manner. For example, as shown in FIG. 9B, the materialdispensing head 436 on the left-hand side of the gantry 418 is inactiveand not used for forming the composite lay-up. Also shown in FIG. 9B,the material dispensing heads 436 on the right-hand side are operatedfor applying strip material 462 to the work surface datum 416 for alonger period or greater portion of the gantry's travels along thetracks 424 than are the material dispensing heads 436 on the left-handside of the gantry 418.

As shown in FIG. 9C, the turntable 480 is rotatable as represented byarrow 493. In this particular embodiment, the turntable 480 has beenrotated one-hundred eighty degrees, which, in turn, allows the materialdispensing heads 436 to apply strip material 462 for forming the otherside portion of the composite lay-up. Or, for example, the turntable 480may be rotated to change the orientation of the work surface datum 416,which, turn, allows the material dispensing heads 436 to apply stripmaterial 462 along a different axis.

The illustrated embodiment of FIG. 9 can be useful for producingrelatively large parts (e.g., empennage skin panels, etc.) where animpractically wide gantry and large number of heads would otherwise beneeded to span the entire part. Accordingly, the illustrated embodimentshown in FIG. 9 has a gantry 418 narrower than the turntable 480 and thepart being formed. Alternatively, other embodiments may include a gantrysupporting less material dispensing heads than that shown in FIG. 9,where the heads are configured to shuttle sideways along the gantry toaccommodate a large lay-up area with a limited number of heads.

Other aspects of the embodiment illustrated in FIG. 9 can be similar toaspects described herein for other embodiments, such as automaticmaterial replacement by material changers (e.g., material dispenserchangers 40 shown in FIG. 1, etc.) and cutters and compactors (e.g.,cutter 102 and compactors 96, 100 shown in FIG. 2, kiss cutting device902 shown in FIG. 15, etc.).

FIGS. 10 through 12 illustrate an exemplary embodiment of a materiallamination device 512 that is well-suited for producing wing stringers,floor beams, narrow spars, and other high aspect ratio parts. As shownfor this particular embodiment, an array or stack of material dispensingheads 536 is deployed along a length (X-axis) of a lay-up table 580. Thestack of heads 536 are configured such that they can collectively swivelas a group, for example, to a positive forty-five degree echelon (e.g.,FIG. 10), a ninety degree echelon (e.g., FIG. 11), a negative forty fivedegree echelon (e.g., FIG. 12), among other angular settings.

As shown in FIG. 10, the material dispensing heads 536 are pivotablysupported from carriages 601 with swivels or pivots 599. The carriages601 are configured for translatable movement along the tracks or rails524. An actuator 603 is provided for causing the material dispensingheads 536 to collectively swivel or pivot as a group.

In this particular embodiment, the swivels or pivots 599 are generallydisposed at the end portions of the material dispensing heads 536.Alternatively, other suitable locations are possible for the swivels andpivots, such as at a generally central location as shown in FIGS. 16Aand 16B.

With continued reference to FIGS. 10 through 12, non-swiveling materialdispensing heads 537A and 537B are respectively disposed to the left andto the right of the array of material dispensing heads 536. In thisparticular embodiment, the material dispensing heads 537 are notprovided with swiveling capability. During operation, the non-swivelingheads 537 can be used for dispensing zero degree strip material or pliesto the lay-up table 580.

As shown in FIG. 10, the material dispensing heads 537 are supportedfrom carriages 605. The carriages 605 are configured for translatablemovement along the tracks 524.

In this particular embodiment, the width of the swiveling materialdispensing heads 536 are an integer multiple of the width of the tape orother strip material being dispensed by the heads 536. Furthermore, thisparticular example includes a stationary lay-up table 580.Alternatively, other embodiments can include a table that moves relativeto the material dispensing heads.

An exemplary operation of the device 512 will now be provided forpurposes of illustration only. In this particular example, a zero degreeply or layer 584 (FIG. 1) is placed by material dispensing head 537B asthe material dispenser 537B moves to the right as represented by arrow585. The material dispensing heads 536 move and follow behind thematerial dispensing head 537B in the direction represented by arrow 585.The material dispensing heads 536 operate in parallel and in unison toplace strip material or tape segments 586 at a positive forty-fivedegrees onto the first ply 584. The carriages 601 advance along theX-axis a distance equal to one tape width, and the material dispensingheads 536 place another set of tape segments onto the first ply 584.This sequence continues until the gaps between the segments of that zoneare filled in. The carriages 601 (and material dispensing heads 536carried thereby) advance along the rails 524 to the next zone whereatthe material dispensing heads 536 then dispense strip material withinthat zone. This process for the material dispensing heads 536 isrepeated until the full ply 586 has been applied to the first layer 584(as shown in FIG. 11).

Now that the ply 586 has been fully applied, the actuator 603 isactuated to cause the material dispensing heads 536 to collectivelyswivel or pivot from the positive forty-five degree echelon (FIG. 10) toa ninety degree echelon (FIG. 11). This swiveling or pivoting of thematerial dispensing heads 536 reduces the width of the tape relative tothe X axis such that the material dispensing heads 536 are now closertogether relative to the X axis.

As shown in FIG. 11, a third layer or ply 588 is placed by zero degreehead 537A as the material dispenser 537A moves to the left asrepresented by arrow 594. The material dispensing heads 536 also move tothe left following behind the material dispensing head 537A in thedirection represented by arrow 594. The material dispensing heads 536operate in parallel and in unison to place strip material or tapesegments 595 onto the third ply 588. These tape segments 595 placed bythe material dispensing heads 536 are perpendicular at a ninety degreeangle relative to the zero degree third layer 588 applied by thematerial dispensing head 537A. The carriages 601 advance along theX-axis a distance equal to one tape width, and the material dispensingheads 536 place another set of tape segments onto the third ply 588.This sequence continues until the gaps between the segments of that zoneare filled in. The carriages 601 (and material dispensing heads 536carried thereby) advance along the rails 524 to the next zone whereatthe material dispensing heads 536 then dispense strip material withinthat zone. This process for the material dispensing heads 536 isrepeated until the full ply 595 has been applied onto the third layer588 (as shown in FIG. 12).

The actuator 603 is actuated to cause the material dispensing heads 536to collectively swivel or pivot from the ninety degree echelon (FIG. 11)to a negative forty-five degree echelon (FIG. 12). This swiveling orpivoting of the material dispensing heads 536 increases the width of thetape relative to the X axis and the pitch between the materialdispensing heads 536.

Plies five and six 596 and 597, respectively, are placed as the heads536 and 537 move to the left as represented by arrow 598. Morespecifically, the zero degree ply 596 is placed by the materialdispensing head 537B. The material dispensing heads 536 (operating inparallel and unison) apply strip material or tape segments 597 at apositive forty-five degrees onto the zero degree ply 596. As before, thecarriages 601 advance along the X-axis a distance equal to one tapewidth, and the material dispensing heads 536 place another set of tapesegments onto the ply 596. Again, this sequence continues until the gapsbetween the segments of that zone are filled in. The carriages 603 (andmaterial dispensing heads 536 carried thereby) advance along the rails524 to the next zone whereat the material dispensing heads 536 thendispense strip material within that zone. This process for the materialdispensing heads 536 can be repeated until the full ply 597 has beenapplied onto the zero degree layer 596.

The above description of an exemplary operation of the device 512 is forpurposes of illustration only and is not intended to limit the scope ofthe present disclosure in any way. The particular operations, processes,and order thereof for the device 512 can depend, for example, on thespecifications for the particular product or article being created bythe device 512.

Other aspects of the embodiment illustrated in FIGS. 10 through 12 canbe similar to aspects described herein for other embodiments, such asautomatic material replacement by material changers (e.g., materialdispenser changers 40 shown in FIG. 1, etc.) and cutters and compactors(e.g., cutter 102 and compactors 96, 100 shown in FIG. 2, etc.). Forexample, in some embodiments, the material dispensers 536 and/or 537 canbe coupled to the respective carriages 601 and 605 by quick releaseconnections or couplings (e.g., coupling 68 shown in FIG. 2, etc.). Insuch embodiments, when a dispensing head is out of tape or otherwiseunserviceable, it can be replaced with a fresh head relatively quickly.Accordingly, this quick change ability can enable relatively highproductivity by reducing machine downtime for tape loading andmaintenance and by allowing tape loading, cleaning, repair and testingto be done offline.

FIG. 13 illustrates an exemplary embodiment of a material compositefabrication device 712 including an array of material dispensing heads736 and a zero degree non-swiveling material dispensing head 737. Asshown in FIG. 13, the material dispensing heads 736 are pivotablysupported above the lay-up table 780 by carriages 701 and swivels 799.The carriages 701 are configured for translatable movement along thetrack or rail 724, which, in turn, is supported by the supportingstructure 727. The zero degree non-swiveling material dispensing head737 is supported above the lay-up table 780 by carriage 705. Thecarriage 705 is configured for translatable movement along the track orrail 724.

With continued reference to FIG. 13, each material dispenser 736 and 737includes strip material rolled onto a spool 790. Each material dispenser736 and 737 also includes a collector spool 716 onto which backing paperfrom the strip material may be wound and stored.

Other aspects of the embodiment illustrated in FIG. 13 can be similar toaspects described herein for other embodiments, such as automaticmaterial replacement by material changers (e.g., material dispenserchangers 40 shown in FIG. 1, etc.) and cutters and compactors (e.g.,cutter 102 and compactors 96, 100 shown in FIG. 2, etc.).

FIG. 14 illustrates an exemplary configuration for a material dispenseror head 836 according to one embodiment of the present disclosure. Thisillustrated configuration may be implemented for any one or more of thematerial dispensing heads (e.g., 36, 436, 536, 537, 736, 737, etc.)shown and described herein).

As shown in FIG. 14, the material dispenser 836 is coupled to thecarriage 801 with swivels or pivots 899. The carriage 801 is configuredfor translatable movement along the tracks or rails 824. Bearings and/orlubrication may also be provided to facilitate sliding movement of thecarriage 801 along the rails 824. In addition, an actuator can beprovided for causing pivoting or swiveling of the material dispensinghead 836 about axis 807 relative to the lay-up table 880.

With continued reference to FIG. 14, the material dispenser 836 operablyhouses strip material 862 (e.g., carbon tape with backing paper, etc.)that is rolled onto a spool 890 in the material dispenser's housing 852.The strip material 862 has a backing paper 892, which may, for example,inhibit undesirable blocking of the strip material 862 as the stripmaterial 862 travels across the various rollers within housing 852during operation of the material dispenser 836.

The strip material 862 can be cut by cutting unit 802 prior toapproaching a release region where the strip material 862 is applied tothe work surface datum. The cutter 802 is configured such that the stripmaterial 862 is cut while leaving the backing paper 892 intact.Accordingly, the backing paper 892 alone exits from the sweep downroller 896 through the serpentine or generally S-shaped path defined bythe sweep down roller 896. The backing paper 892 is then wound onto acollector spool 816. The backing paper 892 can help draw the stripmaterial 862 into the release region of the material dispenser 836. Thebacking paper 892 can help facilitate movement and smooth application ofthe strip material 862 along the work surface datum.

In the particular illustrated embodiment, the material dispenser 836includes a cutter 802 for cutting the strip material 862. A wide rangeof cutting devices and systems can be used for the cutting unit 802 ofthe material dispenser 836, including the cutter 102 shown in FIGS. 2and 5, the kissing cutting device 902 shown in FIG. 15, among othersuitable cutters (e.g., lasers, ultrasonic blades, helical blades,etc.).

The material dispenser 836 also includes a subcarriage 851 that isreciprocally translatable along a horizontal track 895. As describedherein, the subcarriage 851 allows the material dispenser 836 todispense strip material having a predetermined length by movement (asrepresented by arrow 897) of the-subcarriage 851 without requiringmovement of the material dispenser 836 as a whole.

In the particular embodiment shown in FIG. 14, the subcarriage 851includes a sweep down roller 896. The sweep down roller 896 isretractable relative to the table 880 (as shown by the broken linerepresentation of the roller 896). The roller 896 can be retracted whenthe material dispenser 836 is not in use. An actuator 894 is providedfor applying a generally downward force to the roller 896 for causingdownward movement of the roller 896 from its retracted position to anextended position. In the extended position, the roller 896 can operateor roll against the strip material 862 and backing paper 892 beingapplied by the material dispenser 836 for compressing or smoothing thestrip material 862 against the work surface datum. The operation of thesubcarriage 851, actuator 894 and/or movement of the roller 896 can beautomated by computerized controls.

Accordingly, various embodiments of the present disclosure include thetape segment being already in position for placement before the actuallay down process starts. In such embodiments when the lay down starts,only the sweep down roller has to move as opposed to moving the entirematerial dispensing head and its supply and take-up spools as iscommonly required for at least some existing CTLM machines. Alternativeembodiments can include different devices, however, for compacting andsmoothing the strip material, such as the compactors and shoes 96 and100 shown in FIG. 2.

FIG. 15 illustrates an exemplary kiss cutting device 902 capable ofcutting strip material at different angles according to an exemplaryembodiment of the present disclosure. This illustrated cutting device902 may be implemented with any one or more of the material dispensingheads (e.g., 36, 436, 536, 537, 736, 737, 836, etc.) shown and describedherein.

With continued reference to FIG. 15, the kiss cutting unit 902 isconfigured for making cuts through the strip material 962 (e.g., carbontape, etc.) without cutting the backing paper. Unlike some existing CTLMmachines, the kiss cutting unit 902 can make angular cuts on the fly,such as cutting prepreg tape at a positive or a negative forty-fivedegree angle while the prepreg tape is in motion.

The kiss cutting unit 902 includes a blade 906. The blade 906 can berotated relative to the support 907 (and the strip material 962) suchthat the blade 906 is in the angular position shown in FIGS. 15A and15C, or in the angular position shown in FIG. 15B. These two differentangular positions for the blade 906 are about ninety degrees apart forthis particular embodiment, although other configurations are alsopossible.

The blade 906 is also translatable along at least a portion of thelength of the support 907 as shown by a comparison of the bladepositions shown in FIGS. 15B and 15C. The support 907 can also berotated relative to the strip material 962 such that the support 907 canbe positioned as shown in FIGS. 15B and 15C, or in the position shown inFIG. 15A. These two different positions for the support 907 are aboutninety degrees apart for this particular embodiment, although otherconfigurations are also possible.

In the particular illustrated embodiment of FIG. 15, the kiss cuttingunit 902 can provide different angular cuts or cut selections byselectively rotating one or both the blade 906 and the support 907 tothereby change the angle of the blade relative to the strip material962. By coordinating the movements of the blade 906, support 907, andstrip material 962, the blade 906 can make about a ninety degree cut(represented by broken line 903 in FIG. 15A), about a positiveforty-five degree cut (represented by broken line 904 in FIG. 15B), andabout a negative forty-five degree cut (represented by broken line 905in FIG. 15C).

An exemplary operation of the kiss cutting device 902 (FIG. 15) with thematerial dispenser 836 (FIG. 14) will now be provided for purposes ofillustration only. Within the dispensing head 836, carbon tape 862 withbacking paper 892 travels from the supply spool 890 through the cuttingdevice 802 (which in this particular example comprises the kiss cuttingdevice 902) to the sweep down roller 896. The backing paper 892 aloneexits the sweep down roller 896 through the serpentine path and onto thebacking paper take-up spool 816.

This movement of the tape 862 and backing paper 892 through the materialdispenser 836 (and kiss cutting unit 902) can occur under computercontrol. At the appropriate location, the blade 906 of the kiss cuttingunit 906 cuts through the tape 862 but not the backing paper 892. Thetape segment (with the backing paper still attached) moves into positionjust above the lay-up table 880. When the head is in position, the sweepdown roller 896 presses down to the work surface and travels fromright-to-left (as represented by arrow 894). After the tape segment ispressed down to the table 880, the sweep down roller 894 retracts orlifts up (as shown by the broken line representation of the roller 894).The sweep down roller 894 then moves to the right and returns to thestarting position, while pulling the backing paper 892 along with theroller 894.

This particular exemplary method of laying relatively short tapesegments is different and faster than at least some existing CTLMmachines. First, the tape cuts can be made on the fly with the kisscutting device 902. Second, the tape segment is already in position forplacement before the lay down starts. Accordingly, when the lay downstarts, only the sweep down roller has to accelerate and move, asopposed to accelerating the entire head and accelerating the supply andtake-up spools as is done with at least some existing CTLM machines.

The above description of an exemplary operation of the kiss cuttingdevice 902 with the material dispenser 836 is for purposes ofillustration only and is not intended to limit the scope of the presentdisclosure in any way. Alternatively, the kiss cutting device 902 can beused with other material dispensers besides material dispenser 836, andthe material dispenser 836 can include other cutting devices besides thekiss cutting device 902.

FIGS. 16A and 16B illustrate another embodiment of a compositefabrication device 1012 including an array or stack of materialdispensing heads 1036. As shown, the material dispensing heads 1036 aregenerally positioned in a rank and are carried on a rail 1022, which, inturn, is carried by the gantry 1018. The gantry 1018 is configured fortranslatable movement along (X-axis) the tracks or rails 1024. The-rail1022 is configured for translatable movement along (Y-axis) a track 1026defined by the gantry 1018.

In addition, the rail 1022 is rotatably coupled to the gantry 1018 witha generally centrally located pivot or swivel 1099. Accordingly, therail 1022 can be rotated relative to the gantry 1018 (and thus the worksurface datum 1016). When the rail 1022 is rotated relative to thegantry 1018, the material dispensing heads 1036 collectively rotate as agroup relative to the work surface datum 1016, as shown by FIGS. 16A and16B.

In this particular embodiment, the movement of the gantry 1018 along therails 1024 and/or the movement of the rail 1022 (e.g., rotation and/ortranslation) relative to the gantry 1018 can be controlled to change theorientation with which material is laid onto the work surface datum 1016by the material dispensing heads 1036. For example, FIG. 16A shows thematerial dispensing heads 1036 at about a positive forty-five degreeechelon, and FIG. 16B shows the material dispensing heads 1036 at abouta zero degree echelon. The material dispensing heads 1036 may also bepositioned at other angular orientations (e.g., a negative forty-fivedegree echelon, ninety positive or negative ninety degree echelon, etc.)depending, for example, on the particular specifications for thecomposite article.

Other aspects of the embodiment illustrated in FIGS. 16A and 16B can besimilar to aspects described herein for other embodiments, such asautomatic material replacement by material changers (e.g., materialdispenser changers 40 shown in FIG. 1, etc.) and cutters and compactors(e.g., cutter 102 and compactors 96, 100 shown in FIG. 2, kiss cuttingdevice 902 shown in FIG. 15, etc.).

In any of the various embodiments of the present disclosure, the generalmachine configuration may be varied depending on particular needs. Forexample, variations can include increasing or decreasing the number ofmaterial dispensing heads for a particular embodiment, using a movingtable instead of moving heads (and vice versa) for a particularembodiment, varying the width of strip material, using a wheel knifeversus an ultrasonic knife, and/or using an end pivot versus a centerpivot for a material dispensing head.

Aspects of the present disclosure also relate to methods for formingcomposite materials according to the teachings of various embodiments ofthe present disclosure. In one embodiment, a method for fabricating acomposite article generally includes using a plurality of materialdispensers (e.g., 36, 436, 536, 537, 736, 737, 836, etc.), where eachmaterial dispenser dispenses a strip material (e.g., 62, etc.) to a worksurface datum (e.g., 16, etc.) on a structure (e.g., 14, etc.) beneaththe material dispensers. The strip material can be applied to the worksurface datum, such that each material dispenser applies strip materialalong a predetermined axis onto the work surface datum to form a firstlayer (e.g., 84, etc.) having a first orientation. The work surfacedatum can be movable relative to the plurality of material dispensers,and/or the material dispensers can be movable relative to the worksurface datum. Either the work surface datum or the material dispenserscan be rotated, and then strip material can be applied over the firstlayer along a predetermined axis to form a second layer (e.g., 86, etc.)having a second orientation. Such a process may be repeated to applymultiple layers (e.g., 82, etc.). The strip material can be cut by acutting device (e.g., 102, etc.) prior to the relative rotationoperation. Treatment, curing, and/or reacting may follow the applicationof the layers of strip material to the work surface datum. Further, thematerial dispensers can be automatically changed with material dispenserchangers (e.g., 40).

Certain terminology is used herein for purposes of reference only, andthus is not intended to be limiting. For example, terms such as “upper”,“lower”, “above”, and “below” refer to directions in the drawings towhich reference is made. Terms such as “front”, “back”, “rear”, “bottom”and “side”, describe the orientation of portions of the component withina consistent but arbitrary frame of reference which is made clear byreference to the text and the associated drawings describing thecomponent under discussion. Such terminology may include the wordsspecifically mentioned above, derivatives thereof, and words of similarimport. Similarly, the terms “first”, “second” and other such numericalterms referring to structures do not imply a sequence or order unlessclearly indicated by the context.

When introducing elements or features of the present disclosure and theexemplary embodiments, the articles “a”, “an”, “the” and “said” areintended to mean that there are one or more of such elements orfeatures. The terms “comprising”, “including” and “having” are intendedto be inclusive and mean that there may be additional elements orfeatures other than those specifically noted. It is further to beunderstood that the method steps, processes, and operations describedherein are not to be construed as necessarily requiring theirperformance in the particular order discussed or illustrated, unlessspecifically identified as an order or performance. It is also to beunderstood that additional or alternative steps may be employed.

The description of the disclosure is merely exemplary in nature and,thus, variations that do not depart from the gist of the disclosure areintended to be within the scope of the disclosure. Such variations arenot to be regarded as a departure from the spirit and scope of thedisclosure.

1. A method of fabricating a high aspect ratio composite article, themethod comprising: applying a first strip material to a work surfacedatum at a first angle with a first material dispenser; applying aplurality of second strip materials to a work surface datum each at asecond angle with a plurality of rotatable parallel material dispensers;and advancing the first material dispenser and the rotatable parallelmaterial dispensers as a unit the width of the second strip material andcontinuing application of the first strip material by the first materialdispenser and a plurality of second strip materials by the rotatableparallel material dispensers until a desired length is reached.
 2. Themethod of claim 1, wherein the plurality of second strip materials areapplied after the first strip material such that the plurality of secondstrip materials are applied onto of the first strip material forming thework surface datum for the plurality of second strip materials.
 3. Themethod of claim 1, further comprising positioning a predetermined lengthof each of the second strip materials for placement, and then applyingthe predetermined length of each of the second strip materials withoutmoving the rotatable parallel material dispensers as a whole.
 4. Themethod of claim 3, wherein applying the predetermined length of each ofthe second strip materials includes moving a subcarriage along a trackwithin each rotatable parallel material dispenser.
 5. The method ofclaim 1, further comprising selectively cutting the second stripmaterials, without cutting backing material, at a selected one of aplurality of different angles as the second strip materials are moving.6. The method of claim 1, further comprising: reversing direction of thematerial dispensers so the material dispensers travel in the oppositedirection; and applying a third strip material to a work surface datumat the first angle with a third material dispenser that is in-line withthe first material dispenser, but on the other side of the rotatableparallel material dispensers.
 7. The method of claim 6, furthercomprising: rotating the plurality of rotatable parallel materialdispensers to a third angle; applying a plurality of fourth stripmaterials each at the third angle with the rotatable parallel materialdispensers; and advancing the first and third material dispensers andthe rotatable parallel material dispensers as a unit the width of thefourth strip material and continuing application of the third stripmaterial by the third material dispenser and a plurality of fourth stripmaterials by the rotatable parallel material dispensers until a desiredlength is reached.
 8. The method of claim 7, wherein the third angle issubstantially perpendicular to the first angle.
 9. The method of claim7, further comprising: once again reversing the direction of thematerial dispensers so the material dispensers travel in the oppositedirection; applying the first strip material onto the plurality offourth strip materials at the first angle with the first materialdispenser; rotating the plurality of rotatable parallel materialdispensers to a fourth angle; applying a plurality of fourth stripmaterials each at the fourth angle with the rotatable parallel materialdispensers; and advancing the first and third material dispensers andthe rotatable parallel material dispensers as a unit the width of thefourth strip material and continuing application of the first stripmaterial by the first material dispenser and a plurality of fourth stripmaterials by the rotatable parallel material dispensers until a desiredlength is reached.
 10. The method of claim 9, wherein a multiple plylayup is formed with layers of material at the first angle, the secondangle, the third angle, and the fourth angle with as many subsequentlayers as desired.
 11. The method of claim 9, wherein the first angle issubstantially parallel to the direction of travel of the materialdispensers, the second angle is about positive forty-five degreesrelative to the first angle, the third angle is about ninety degreesrelative to the first angle, and the fourth angle is about negativeforty-five degrees relative to the first angle such that a multiple plylayup is formed having a first zero degree layer, a forty-five degreelayer on top of the first zero degree layer, a second zero degree layeron top of the forty-five degree layer, a ninety degree layer on top ofthe second zero degree layer, a third zero degree layer on top of theninety degree layer, and a negative forty-five layer on top of the thirdzero degree layer.
 12. The method of claim 1, wherein the first stripmaterial is dispensed from a first supply of strip material onboard thefirst material dispenser, and wherein each of the second strip materialsis dispensed from a second supply of strip material onboard acorresponding one of the rotatable parallel material dispensers.
 13. Adevice for fabricating a high aspect ratio composite article, the devicecomprising: a plurality of material dispensers movable relative to astructure having a work surface datum, each material dispenser operablefor applying strip material to the work surface datum along apredetermined axis; the plurality of material dispensers including atleast a first material dispenser, at least a second material dispenserin-line with the first material dispenser, and a plurality of materialdispensers substantially parallel with each other, the parallel materialdispensers disposed generally between and at an angle to the first andsecond in-line material dispensers; the first and second in-linematerial dispensers translatable relative to the work surface datum suchthat the first and second in-line material dispensers can apply stripmaterial to the work surface datum along a predetermined axis, in onedirection and then the opposite direction; and the parallel materialdispensers rotatable about a vertical axis and translatable relative tothe work surface datum such that the parallel material dispenses can berotatably positioned for applying strip material at predetermined axesthat are not parallel to strips applied by the first and second in-linematerial dispensers.
 14. The device of claim 13, wherein at least one ofthe parallel material dispensers further comprises a track and asubcarriage translatable along the track and operable for dispensing apredetermined length of strip material by movement of the subcarriagewithout requiring movement of the material dispenser head as a whole.15. The device of claim 14, wherein the subcarriage comprises aretractable roller, and an actuator for causing movement of theretractable roller between a retracted position and an extendedposition.
 16. The device of claim 13, wherein at least one of thematerial dispensers includes a kiss cutting device operable forselectively cutting strip material, without cutting backing material, ata selected one of a plurality of different angles as strip material ismoving relative to the cutting device.
 17. The device of claim 13,wherein at least one of the material dispensers includes: at least onesupport selectively rotatable between at least two angular positionsrelative to the strip material; and at least one blade coupled to thesupport such that the blade is translatable along at least a portion ofthe support and selectively rotatable relative to the support between atleast two angular positions; the selective positioning of the supportand the blade allowing cutting of material at a selected one of aplurality of different angles.
 18. The device of claim 13, wherein thefirst and second in-line material dispensers have fixed angularorientations relative to the work surface datum such that the first andsecond in-line material dispensers can only apply strip material to thework surface datum along a single predetermined axis.
 19. The device ofclaim 18, wherein the angular orientations of the first and secondin-line material dispensers are fixed such that the first and secondin-line dispensers can only apply strip material to the work surfacedatum along an axis parallel with the direction of translatable movementof the first and second in-line material dispensers, whereby stripmaterial applied by the first and second in-line material dispensersform zero degree layers.
 20. A method of fabricating a high aspect ratiocomposite article, the method comprising; applying a plurality of stripmaterials to a work surface datum each at an angle with a plurality ofparallel material dispensers by: selectively cutting predeterminedlengths of the strip materials, without cutting backing material, at anangle corresponding with the angle at which the plurality of stripmaterials will be applied to the work surface datum; positioning the cutpredetermined lengths of strip materials for placement to the worksurface datum; applying the cut predetermined lengths of strip materialsto the work surface datum without moving the parallel materialdispensers as a whole; advancing the parallel material dispensers as aunit the width of the strip material and continuing application of aplurality of strip materials by the parallel material dispensers until adesired length is reached.